The invention relates to an x-ray diagnostic generator in which the x-ray tube voltage is adjustable via the x-ray tube current, and hence via the voltage drop at the generator internal resistance, and, for establishing the respective voltage versus current relationships (load lines), at least one series resistance is connected in the power path between the mains and the x-ray tube, and in which means are present for switching the x-ray tube on and off.
An x-ray diagnostic generator of this type is described, for example, in the German AS No. 1,137,144. In modern x-ray diagnostics the demand exists for making possible the briefest possible switching times; i.e., the briefest possible radiographs. However, in the case of an x-ray diagnostic generator of the cited type, downward limits are set on the switching time by the series resistance, which establishes the dependency of the x-ray tube voltage upon the x-ray tube current. The series resistance, namely prolongs the leading edge of the x-ray tube voltage and hence the briefest possible switching time. Accordingly, in this instance, very brief switching times are possible only in the case of high power and, accordingly, low series resistance.